Global Patent Index - EP 0565306 A1

EP 0565306 A1 19931013 - Modulator-based lightwave transmitter.

Title (en)

Modulator-based lightwave transmitter.

Title (de)

Lichtwellensender mit Modulator.

Title (fr)

Emetteur d'ondes optiques avec modulateur.

Publication

EP 0565306 A1 19931013

Application

EP 93302572 A 19930401

Priority

US 86661692 A 19920410

Abstract (en)

An externally modulated laser-based transmitter is disclosed which utilizes an automatic bias control (ABC) circuit (40) to maintain the bias voltage applied to the external modulator (10) at a predetermined level required to provide the necessary separation between logic levels. The ABC circuit generates a dither signal and functions to digitally compare the phase of the dither signal to the phase of the optical signal produced by the external modulator. A phase comparator (e.g., D-type flip-flop) is used to monitor any drift in the optimum bias point of the modulator and generate an output correction signal by continuously adjusting the level of the DC bias voltage applied to the external modulator. <IMAGE>

IPC 1-7

G02F 1/03; G02F 1/225; H03D 13/00; H04B 10/14

IPC 8 full level

H04B 10/04 (2006.01); G02F 1/01 (2006.01); G02F 1/03 (2006.01); G02F 1/035 (2006.01); H04B 10/06 (2006.01); H04B 10/14 (2006.01); H04B 10/155 (2006.01)

CPC (source: EP US)

G02F 1/0123 (2013.01 - EP US); H04B 10/505 (2013.01 - EP US); H04B 10/50575 (2013.01 - EP US); H04B 10/588 (2013.01 - EP US)

Citation (search report)

  • [X] EP 0444688 A2 19910904 - FUJITSU LTD [JP]
  • [X] US 3579145 A 19710518 - LANGE OWEN E DE
  • [Y] EP 0355330 A2 19900228 - ANT NACHRICHTENTECH [DE]
  • [Y] US 4754260 A 19880628 - NELSON ROBERT G [US], et al
  • [A] GB 1523879 A 19780906 - POST OFFICE
  • [X] KAO M. L., ET AL.: "2.5 GBIT/S TI : LINBO3 EXTERNAL MODULATOR TRANSMITTER AND ITS LONG DISTANCE TRANSMISSION PERFORMANCE IN THE FIELD.", ELECTRONICS LETTERS, IEE STEVENAGE., GB, vol. 28., no. 07., 26 March 1992 (1992-03-26), GB, pages 687 - 689., XP000291620, ISSN: 0013-5194, DOI: 10.1049/el:19920434
  • [X] PATENT ABSTRACTS OF JAPAN vol. 2, no. 82 (E-41)30 June 1978 & JP-A-53 047 701 ( NTT ) 28 April 1978
  • [X] RADIO ENGINEERING AND ELECTRONIC PHYSICS vol. 15, no. 9, 1970, WASHINGTON US pages 1659 - 1662 V. YA. SAVEL`YEV 'Electronic Stabilization of the Operating Point of an Electro-Optical Light Modulator with Low Control Voltages'
  • [A] SOVIET INVENTIONS ILLUSTRATED Section EI, Week 8513, 8 May 1985 Derwent Publications Ltd., London, GB; Class U23, AN 85-079532/13 & SU-A-1 109 871 (ELEC AGGREGRATE) 23 August 1984

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

US 5208817 A 19930504; EP 0565306 A1 19931013; JP H0629603 A 19940204

DOCDB simple family (application)

US 86661692 A 19920410; EP 93302572 A 19930401; JP 10602593 A 19930409